zanzabar
Posts: 38
Joined: Tue Jun 04, 2019 12:46 pm
Location: Petaluma, CA

Re: Driving in B mode often can cause issues?

Fri Nov 01, 2019 12:36 pm

mpulsiv wrote:
Fri Nov 01, 2019 11:57 am
I fail to understand why bother with regen.
One pedal driving obviously! I like not having to move my foot over to the brake pedal if I don't have to.
His: 2007 Volvo V70 (185k miles)
Hers: 2019 e-Golf SE (11k miles, black, all stock)
Former: 2016 e-Golf SE (silver, lowered on H&R Sport springs, 225/55 tires on 16" Konig wheels [sold])

mpulsiv
Posts: 44
Joined: Mon Apr 22, 2019 2:17 pm

Re: Driving in B mode often can cause issues?

Fri Nov 01, 2019 1:10 pm

zanzabar wrote:
Fri Nov 01, 2019 12:36 pm
mpulsiv wrote:
Fri Nov 01, 2019 11:57 am
I fail to understand why bother with regen.
One pedal driving obviously! I like not having to move my foot over to the brake pedal if I don't have to.
Makes sense. There are slew of drivers with 3 pedals nostalgia. The technology is reducing user interaction :geek:
On a relevant note, I still think that new drivers should learn to drive a stick. This is the most effective learning curve to feel the car and stay relaxed. Majority of drivers behind the wheel are way too tense. Tension leads to fear. With all the technology at our disposal, drivers still stuck in 2-dimensional world. 97% of their attention is through the windshield. Anyways, I have no intension to derail discussed topic. Just wanted to chime in about driver awareness and interaction as we shift into the future with 1 pedal driving :mrgreen:
VW CEO: “Anything Tesla Can Do, We Can Surpass”
Take your foot off the pedal when shift modes (e.g. D1, D2, D3, B) due delay in re-calibration.
Weight distribution: F = 54%, R = 46%
Spring rates: F = 135 lbs/in, R = 215 lbs/in
0.27 Cd (drag coefficient)

Szyszka
Posts: 71
Joined: Fri Sep 06, 2019 8:31 am

Re: Driving in B mode often can cause issues?

Sat Nov 02, 2019 4:24 pm

mpulsiv wrote:
Fri Nov 01, 2019 11:57 am
I fail to understand why bother with regen. After all, your brake pads don't come into play until your braking demand exceeds the stopping force of the regen system. As soon as you touch the brake pedal, regen kicks in sequential order: D1 -> D2 -> D3 -> B -> your brake pads. So, why bother?

On a different note, here's the screenshot from the owner's manual. If I understand this correctly, we must take foot off the pedal when switch drive modes (e.g. D1, D2, D3, B) due delay in re-calibration. Please chime in.

Image
I am by no means regen braking expert but do not agree with the sequence you provided ( "As soon as you touch the brake pedal, regen kicks in sequential order: D1 -> D2 -> D3 -> B -> your brake pads). When you touch the brake pedal, you DO START engaging the brake pads. On the contrary, brakes are NOT used when slowing using any of the four regen modes (D1, D2, D3, and B).

As for your understanding of the manual, again, I think you're reading it incorrectly. The note about not accelerating when moving the selector surely applies to the 'move' between P, R, N, and D. I would argue that switching between D and D1/D2/D3 and B modes are precisely that: 'switches' and the annotation you're reading has nothing to do with those.

f1geek
Posts: 918
Joined: Fri Jan 23, 2015 1:18 pm
Location: SF Bay Area

Re: Driving in B mode often can cause issues?

Sat Nov 02, 2019 4:37 pm

When you press on the brake pedal, the brake pads will not engage unless the deceleration you require (indicated by how hard you press the pedal) is greater than can be provided by regen. The e-Golf has a blended regen/frction braking system and will only engage friction brakes (pads) when the computer senses you can't stop fast enough via regen. There is no sequence of D3-D2...etc. Those driving mode are for the level of regen you get when you lift your foot off the accelerator pedal - those mode have nothing do do with the brake pedal.

As far as moving the shift level during acceleration, I move the level from D to B or left or right all the time, including when accelerating and decelerating. I haven't noticed any loss of control, though I am only pulling it back or moving it left or right.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior

mpulsiv
Posts: 44
Joined: Mon Apr 22, 2019 2:17 pm

Re: Driving in B mode often can cause issues?

Mon Nov 04, 2019 11:52 am

I think this is somewhat accurate. Watch the needle when you hit the brake to determine if your brake pads come into play.
Needle can fluctuate based on terrain when coasting downhill.

Image
VW CEO: “Anything Tesla Can Do, We Can Surpass”
Take your foot off the pedal when shift modes (e.g. D1, D2, D3, B) due delay in re-calibration.
Weight distribution: F = 54%, R = 46%
Spring rates: F = 135 lbs/in, R = 215 lbs/in
0.27 Cd (drag coefficient)

JoulesThief
Posts: 2576
Joined: Mon Oct 05, 2015 2:01 pm

Re: Driving in B mode often can cause issues?

Mon Nov 04, 2019 8:02 pm

I can regenerate clear to the 6th mark in the green, the limit, putting the car in D3 coming down a 6% grade at 65 mph, without touching the brake pedal. A lot of it depends on how fast you are travelling when you apply the various D modes or B mode.
2015 e-Golf SEL
2015 Passat TDI SEL
2014 Touareg TDI LUX

Full spectrum VW owner, life is too short to wait to drive for a recharge.

in2insight
Posts: 45
Joined: Sun Nov 23, 2014 1:20 pm

Re: Driving in B mode often can cause issues?

Tue Nov 05, 2019 5:28 pm

Szyszka wrote:
Thu Oct 31, 2019 12:10 pm
in2insight wrote:
Thu Oct 31, 2019 8:20 am
I drive mostly in D2, sometimes in B.
Question, when shifting from B back to D why does the shifter go to N first?
I tried to find the answer in the manual, but came up short.


Wait, how are you shifting from B to D? You're supposed to tap it backward, not forward. Are you pushing it forward and therefore into N?
(Bows head in shame) Yes, I was pushing forward. Thank you for kindly giving me the correct way to do so.

mpulsiv
Posts: 44
Joined: Mon Apr 22, 2019 2:17 pm

Re: Driving in B mode often can cause issues?

Tue Nov 05, 2019 5:47 pm

I find interesting how rear brakes are more engaged just by observing the brake dust. I'm seeing way more dust in the rear :shock:
Typically, rear brakes on ICE cars are used ~30% and exhibit way less dust compared to front brakes.
VW CEO: “Anything Tesla Can Do, We Can Surpass”
Take your foot off the pedal when shift modes (e.g. D1, D2, D3, B) due delay in re-calibration.
Weight distribution: F = 54%, R = 46%
Spring rates: F = 135 lbs/in, R = 215 lbs/in
0.27 Cd (drag coefficient)

f1geek
Posts: 918
Joined: Fri Jan 23, 2015 1:18 pm
Location: SF Bay Area

Re: Driving in B mode often can cause issues?

Tue Nov 05, 2019 5:58 pm

My e-Golf has almost no front brake dust on the wheels ( I just hand washed the car and had a very close look at the wheels). Rear wheel brake dust is caused by low speed stopping, and VW has a rear brake bias for very low speed brake usage, as also evidenced by brake sound coming from the rear of car at ~5 mph or less stopping. Front brakes show very little dust because almost no braking is done by front brakes any speed (unless you panic brake at highway speeds). This is why I don't believe the whole D3-D2-D1, etc. regime is correct - I think the friction brakes don't get applied unless the needle is pegged at max "green" and the brake pedal pressure indicates to the computer more deceleration is needed.
2017 e-Golf LE, Multi Coat White with Black Vegan Leather interior

JoulesThief
Posts: 2576
Joined: Mon Oct 05, 2015 2:01 pm

Re: Driving in B mode often can cause issues?

Thu Nov 07, 2019 8:45 am

f1geek wrote:
Tue Nov 05, 2019 5:58 pm
I think the friction brakes don't get applied unless the needle is pegged at max "green" and the brake pedal pressure indicates to the computer more deceleration is needed.
/\ This is correct. I almost never get brake dust on either front or rear wheels, as noted when washing the car and the rims. Early on in ownership, I took the e-Golf through the twisty canyon roads here and did use the brake somewhat aggressively, pegging the needle in the green, and sure enough, I would have to scrub the brake dust off of rear wheels on the next car wash.

This was valving and setup on a 2015... I do not know if they've changed the valving on newer 2019's.

You do have to peg the needle in the green, going counter clockwise, and then push on the brakes just bit more to get that rear brake dust.
2015 e-Golf SEL
2015 Passat TDI SEL
2014 Touareg TDI LUX

Full spectrum VW owner, life is too short to wait to drive for a recharge.

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